updated for version 7.3.1149
Problem:    New regexp engine: Matching plain text could be faster.
Solution:   Detect a plain text match and handle it specifically.  Add
            vim_regfree().
diff --git a/src/ex_getln.c b/src/ex_getln.c
index 6fe9148..4bebe23 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -4717,7 +4717,7 @@
 	    }
     }
 
-    vim_free(regmatch.regprog);
+    vim_regfree(regmatch.regprog);
 
     return ret;
 #endif /* FEAT_CMDL_COMPL */
@@ -5785,7 +5785,7 @@
 	if (history[histype][idx].hisstr == NULL)
 	    hisidx[histype] = -1;
     }
-    vim_free(regmatch.regprog);
+    vim_regfree(regmatch.regprog);
     return found;
 }